Clamping ring for expansible tools



May 12, 1925. 1,537,202

F. SWAN K CLAMPING RING FOR EXPANSIBLE TOOLS Original Filed Feb. 9. 1924 2 Sheets-Sheet 1 gfluantoz Frez/ 5mm.

May 12, 1925. 1,537,202

F. SWAN 1 CLAMPING RING FOR EXPANSIBLE TOOLS Original Filed Feb. 9, 1924 2 Sheets-Sheet 2 5 Fr ed 5mm.

Patented May 12, 1925.

UNITED STATES PATENT OFFICE.

FRED SWAN, OF MARIETTA, OHIO.

CLAMPING RING FOR EXPANSIBLE TOOLS.

I Application filed February 9. 1924, Serial No. 691,725. Renewed April 3, 1925.

To all whom it may concem:

Be it known that zen of the United States, residing at Marietta, in the county of Washington and State of Ohio, have invented certain new and useful Improvements; in Clamping Rings for Expansible Tools, of which the following is a specification, reference being had to the accompanying drawings, forming a part thereof. I

My invention relates to clamps for holding the cutters of expansible well drilling tools in closed posltion, and has for its object to provide a device for this purpose adapted to rest upon the upper end of casing when the tool is in the well and to fit over the cutters as the tool is withdrawn through the casing and clamp them 'in closed position and so hold them until the tool is again introduced into the casing In under reamers of Swan under reamer type and other under-reamers and expansible drills in which the cutters move from collapsed position into expanded operating position by being drawn upward after the tool is lowered below casing, to ride upon a wedge or are otherwise drawn up so that their inner face rest against fixed abutments, it is necessary'in order to introduce the tool into the well casing .to draw the cutters down on the tool body and hold them in collapsed position until lhe tool is lowered into the upper end of thecasing, and whenever the tool is withdrawn from the casing the operation of drawing down the cutters and securing them in collapsed position must be repeated.

It is the object of my invention to provide a device which will rest upon the upper end of the casing in position to serve as a protection for the threads of the coupling at such upper end and which, as the underreamer or other collapsible cutter tool is withdrawn, will extend about the cutters and hold them against springing out as they would otherwise do as they are drawn up above the upper end of the casing.

lVith the objects above indicated and other objects hereinafter explained in View, my invention consists in the construction and combination of elements hereinafter described and claimed.

I, FRED SWAN, a citi- Referring to the drawings: Figure 1 shows in vertical sectional view a portion of the upper end of a well casing showing a clamp embodying my invention in position ready to operate to clamp reamer within the well casing,

Figure 4: is a sideview of the upper end of a well casing showing how the clamp may be placed, in position for use.

Figure 5 is a vertical sectional view of the. upper end of a well casing showing a modified form of clamp in position.

Figures 6, 7 and 8 show the clamps in top plan, side elevation and vertical section respectively. Y

In the drawings 1 indicates the upper section of a well casing having at its upper end the usual threaded coupling ring 2.

3 indicates an under reamer having the bits or cutters 4, 4, in collapsed position, that is drawn down to the lower end of the reamer body below the lower end of the wedge 5 in order that the tool may be passed through the casing, it being understood that when the tool is lowered below the lower end of the casing the cutters will by the action of the usual spring, '(not shown) be drawn upward with their inner faces against the faces of the wedge 5 until their upper ends are in contact with the abutments 6, this causing the cutters to be expanded to the proper diameter to ream out the hole below the casing to the size required to permit the casing to be lowered.

Ordinarily as the under reamer is drawn out of the casing, as soon as the cutters are above the casing they will be drawn upward on the wedge into expanded position and in order to again lower the tool into the casing the cutters must be ,drawn down into collapsed position and held insuch position until they are lowered within the upper end of the casing.

well within the casing is necessary in order to prevent injury to the threads of the coupling ring 2.

The clamp of my invention consists of a ring 7 having its inner diameter the same as that of the inner diameter of the easing and having its outer diameter equal to and preferably greater than the outer diameter oi? the coupling ring 2 so that it will rest upon the upper edge of this coupling ring. From this ring 7 and integral with it depends an annular flange 8 having its inner diameter continuous with the inner diameter of ring 7 and of the same diameter as that of the interior of the casing and having its exterior diameter slightly less than the interior diameter of the coupling 2 so that when the lower edge of the ring 7 rests on the upper edge of the coupling 2 this flange 8 extends downward inside the coupling nearly to the upper end ofthe casing and protects the threads of the coupling above the end of the casing from abrasion.

The clamp is provided with an opening 10 extending through the ring 7 and flange 8 preferably oblique to the axis as shown in Figure 7 so that the clamp may be readily placed on or removed from the drill rope 11 by tilting it as shown, sli ping the rope through the opening 10 and t en turning the clamp back into normal position and permitting the flange 8 to drop into the upper end of coupling 2. This oblique slot prevents drilling line from fouling in slot, while resting on coupling as shown in Figure 7 represented by dotted lines.

The clamp being thus in position on the coupling 2 and the under reamer being down in the wall below the casing, the first effect of drawing the drill rope upward is that as the cutters strike the lower end of the casing they are stopped, and as the reamer body is further raised, the wedge 5 is drawn upward -from between them and they move inward into collapsed position so that they can enter the casing. As the under reamer is raised through the casing the cutters are held in collapsed position by the walls of the casing. Vi hen the upper edges of the cutters pass the upper edge of the upper section of the casing they enter within the flange 8 and pass nearly through theclamp. As the lower edges of the cutters pass above the upper edge of the casing the force of the spring which tends to draw the cutters upward on the wedge will cause the cutters to expand outward sufficiently to force them against the walls of the flange 8 so that as the under reamer is raised further to permit it to clear the casing it will carry the clamp with it and the clamp will remain in position holding the cutter in collapsed position until forcibly removed.

hen the under reamer is to be returned to the well its lower end is brought in line with the casing and, as it is lowered its lower end carrying the clamp enters the upper end of the casing the flange 8 slipping down inside the coupling 2 until ring 7 rests on the upper edge of the coupling. This stops further movement of the clamp and the end of the under reamer slips readily into the easing In Figure 5 I have shown the inner face of the ring 7 coned out to form a guide for a bit 12 or for use as a funnel to guide in pouring water into the well hole.

It should beunderstood that the clamp is not limited to use with the Swan under reamer or to use with any particular under reamer or other drilling tool with collapsible cutters as it is adapted and intended for use with an under reamer or collapsible cutter tool in w 'ch the cutters ride upward into expanded position.

Having thus escribed my invention what I claim is 1. A clamp for well drilling tools ada ted to enclose expansible cutters and hold t em in closed posltion comprising a ring having its inner diameter substantially that of the inner diameter "of the well casing, ada ted to rest upon the upper edge of the coup in at the upper end of the casing and provide with means for engaging said coupling to hold. it concentric therewith.

2. A clamp for well drilling tools adapted to enclose expansible cutters and hold them in closed osltion comprising a ring having its inner iameter substantially that of the inner diameter of the well casing, adapted to rest upon the upper edge of the coupling at the upper end of the casing and provided with means for engaging the inner face of said coupling to hold it concentric therewith.

3. A clamp for well drilling tools ada ted to enclose expansible cutters and hold 1; em in closed position comprising a ring having its inner diameter substantially that of the inner diameter of the well casing, ada ted .to rest upon the upper edge of the coup ingat theupper end of the casing and provided with an annular flange extending downward therefrom adapted to enter said coupling to hold the ring concentric therewith.

4. A clamp for well drilling tools adapted to enclose expansible cutters and hold them in closed position comprising a ring having its inner diameter substantially that of the inner diameter of the well casing, adapted .to rest upon the upper edge of the coupling at the upper end of the casing and provided with an annular flange extending downward therefrom having its outer diameter less than the inner diameter of the coupling and adapted to enter within the screw threads thereof to hold the ring concentric with the coupling.

5. A clamp for well drilling tools adapted to enclose expansible cutters and hold them in closed position comprising a ring having its diameter substantially that of the inner diameter of the well caslng, adapted to rest upon the upper edge of the coupling at the upper end of the casing and provided with means for engaging said coupling to hold signature.

FRED SWAN. 

